Tumor Biopsy Techniques - APMA Region 1 November, 2006
Biopsy - Definition
Removal of representative sample of a tumor or lesion for pathological analysis
Biopsy - Goals
Achieve an accurate diagnosis
Formulate a treatment plan
Far Side
Overall Flow Chart
Soft tissue tumors
Beware
80% misdiagnosed
60% inadequate margins after unplanned excision
Unplanned Surgical Removal
< 2 CM - Evaluation
Superficial
No critical structure nearby
No work up required
Pathology, not biopsy
< 2 CM - Excision with Path
Wide excision c/w function and healing
Excise tumor, capsule, cuff
Avoid ‘shelling out’
Why send it to path?
The pathologist is your back-up
If the lesion is malignant, the limb can be salvaged
> 2 CM Evaluation
> 2 CM - MRI and Xray
Plain radiographs
Bone involvement
Diagnostic features
MRI
Anatomic extent
MRI features may help identify the lesion
The radiologist is your back-up
> 2 CM - Known or Characterizable
The MRI features allow identification of the lesion
Lipoma
PVNS
Hemangioma
Ganglion cyst
85% correct
Excise
> 2 CM Unknown or Uncharacterizable
The features of the MRI do not allow identification of the lesion with a high degree of
certainty
Synovial sarcoma
Clear cell sarcoma
Epithelioid sarcoma
Uncharacterizable by MRI
Biopsy is the last step
Biopsy only
Open Biopsy - General Techniques
Incision size
Use the smallest longitudinal incision that allows a full view of your goal
Tourniquet use
Do not exanguinate
Release prior to closure
Open Biopsy - General Techniques
Do not raise flaps
Do not retract more than needed
Do not use intramuscular planes
Do not dissect, simply incise with the bovie on cautery
Open Biopsy - General Techniques
Incise directly down - thin layer by thin layer with the bovie
Color change red to salmon
Salmon to grey or tan/white
Biopsy the tumor not the capsule
Cut a cube out with the knife
Biopsy – Closing the Deal
Make sure the wound will stay closed
Splints, casts or pressure dressings
Postoperative activity restriction
Three Kinds of Bone Tumors
Latent
No pain or symptoms prior to discovery
Narrow zone of transition, sclerotic rim, no periosteal reaction, no soft tissue mass
Latent bone tumors
Non-ossified fibroma
Enchondroma
Lipoma
Unicameral bone cyst
Latent Lesions May Be Observed Without Biopsy
Diagnosis by history and imaging studies
Biopsy not required to confirm diagnosis
Tumor poses no risk to the pt.
Observe 12-24 months
Active
Bone tumors with active appearance
Giant cell tumor
Aneurysmal bone cyst
Chondromyxoid fibroma
Chondroblastoma
Active lesions require biopsy
Growth and damage
Treatment plan needed
Biopsy required
Biopsy will lead to correct treatment plan
Biopsy and removal as staged procedures
Aggressive
Progressive growth but only moderate pain
Moth-eaten or permeative appearance, wide zone of transition, marked periosteal
reaction, extensive cortical destruction, soft tissue mass
Management of aggressive bone lesions
Staging studies needed
MRI, CT, CCT, BS, Labs
Biopsy required
Biopsy will lead to correct treatment plan
Biopsy and removal as staged procedures
Osteoblastoma
Ewing sarcoma
Osteosarcoma
Chondrosarcoma
(Infection)
Work-up: Xray /MRI / CT / BS
Complete imaging studies before biopsy
Xray + MRI for soft tissue lesions
Xray + CT (MRI) for bone lesions
Additional studies based on the differential diagnosis
Children’s Bone and Soft Tissue Tumors
Special tumors, problems, and risks
Chondromyxiod fibroma
Osteoid osteoma, osteoblastoma
Ewing sarcoma
Tumors in Children should be referred to a subspecialist
Ewing’s
Hindfoot -33% survival
Forefoot – 70% survival
With mets – 0%
Refer
Non-Tumors (PVNS)
PVNS
Gout
Stress fracture or missed fracture
Subchondral cyst
Gout, Stress Fracture
Non tumors – biopsy not necessary
Diagnosis based on labs, imaging studies, serial xrays, etc
Biopsy often unrewarding
Biopsy Only -Without Removal
Allows the pathologist the time needed
Prepares the surgeon and the patient for the definitive treatment
Reduces risk
Bone Biopsy - General Techniques 1
Incision size
Use the smallest longitudinal incision that allows you a full, unimpeded view of your
goal
Tourniquet use
Controversial
Do not exanguinate with an Esmarch
Release prior to closure
Hazards of Biopsy
Biopsy has many potential complications:
Nondiagnostic material
Errors in interpretation of histological material
Contamination of uninvolved compartments or spread of tumor in hematoma
Bone Biopsy - General Techniques 4
Drill a round hole
Make it into an oval as needed
Avoid stress risers
Biopsy - General Techniques 5
The purpose of the frozen section is to make sure you have adequate tissue for diagnosis
“Biopsy all cultures, culture all biopsies”
Hopefully the pathologist will receive the sample fresh
Biopsy - General Techniques 6
Biopsy - General Techniques 7
Make sure the wound will stay closed
Splints, casts or pressure dressings
Postoperative activity restriction
Biopsy of Soft Tissue Tumors - Special Considerations
Unplanned excision of soft issue tumors leads to cancer being left behind
35% had residual tumor (Noria JBJS 1996)
Important staging data were unavailable
The chance of misdiagnosis and mismanagement is much higher
Seems to be highest with small subcutaneous masses
Complications of Biopsy
MSTS studies in 1982 and 1996
14% major error rate
errors twice as likely in outside biopsies
19% resulted in an alteration in care
Amputations in 5%
No change in 14 years!
MSTS Study
Mankin et al, MSTS 1982 - 329 pts
Major errors in diagnosis 18.2%
Complications occurred in 17.3%
4.5% had unnecessary amputation
Mankin et al, MSTS 1996 - 597 pts
Major errors in diagnosis 13.5%
Complications occurred in 15.9%
3% had unnecessary amputation
MSTS Study
Adverse events were far more frequent when biopsy was preformed in the referring
institution
Recommendation in both studies was that biopsy of sarcomas should be performed in a
musculoskeletal tumor center
Hazards of Biopsy
Biopsy has many potential complications:
Nondiagnostic material
Errors in interpretation of histological material
Contamination of uninvolved compartments or spread of tumor in hematoma
CPT Codes for Tumors
Reasons Not to Do a Biopsy
A Biopsy is Not…
Hazards of Biopsy
Biopsy is Not a “No-Brainer”
Preparing the Patient
Preparing the OR & Staff
“To urinquet” or not?
Surgical Approach
Sampling the Lesion
Hemostasis and Closure
Post-op Care
www.bonetumor.org/APMA/
Thank You